Just kinda looking at pics, it looks like you can upgrade RAM, CPU, and Harddrive. The Graphics is hidden under the body, so Asus probably did what they've done with every notebook so far... it's soldered to the mobo.

memory, two slots, available under a cover in the bottom of the machine
i have maxed the ram in my G1 to 4Gb. 2x 2gb DDR2 667Mhz PC5300
32bit vista only sees 2.87Gb, 64bit vista untested yet.
i could argue the "what you get for your money" line, but i got these in return for some other stuff, so the cost was negligable on my part.

Hard disk, available under a cover in the bottom of the machine.
i don't see the point in upgrading the hard disk (160Gb) just yet, but it is possible. can only get 200Gb, as the 240Gb'ers arn't available outside OEMs at the moment, and the price for an extra 40Gb storage on the 200Gb'ers isn't worth it.

Graphics, i havn't had the ballski's to crack the case on it yet to have a look.
going by hope, i "hope" that it uses the MXM standard for laptop GFX cards. nothing out at the moment makes me feel the price performance ratio is worth it over the GF7700 that is already in there, untill the GF8x00 cards hit the stores. if it uses MXM, then you can take it out and put in a GF7900GS
for a 10-50% performance gain.

CPU, again, not had a look. but other laptops seem upgradable. but then...
the T7600 is the same chip as the T7200 only running at 333Mhz faster. but would cost Â£400(UKP) to replace. is it worth it? not really. not untill the retail channel gets the new 800/1066FSB mobile cpu parts, and they chop the price of the 2.33Ghz T7600 to clear old stock of 667Mhz FSB cpu parts.

ok, so i got bored one day and cracked open my Asus G1
the GFX is not upgradable. boo. the Nvidia go7700 and go8600 in the more recent G1's is soldered to the mainboard.
unless you wanna get freaky and unsolder the chip, trace which solder pads are the PCIe slot and video outputs, solder some fly leads from the solder pads to an MXM connector and fit a m8800gtx...
if you want MXM in a 15" laptop, i belive the current alienware chassis has an m8800gtx on an MXM type3 card...
the CPU is upgradeable to a T7600 2.33Ghz, as it falls within the same 35watt TDP as the T7200.
i dunno why asus didn't max it out to begin with... just don't think you'll fit the newer 800Mhz fsb socket 439 cpus in there Edited by darksun9210 - 6/25/08 at 8:33am

I'm trying to upgrade a G1S's hard drive for a friend of mine, and for the life of me, I can't quite get into the internals. I get so tantalizingly close, but no cigar. I haven't had any luck finding a disassembly guide online. Any guidance and direction would be most appreciated, darksun.

too bad the gfx is not upgradable. apparently there is a batch of the G1 line taht has faulty gfx, and mine is in that batch. it cause the gfx to overheat and makes game fps drop. asus and nvidia know about the problem but won't do a thing about it.